The Power of Truth

“I will ask the Father, and He will give you another Advocate to be with you forever — the spirit of truth. The world cannot receive it, because it neither sees it nor knows it. But you do know it, for it abides with you and will be in you.” (John 14:16-17)

The word "spirit" refers to power of truth.  

"Jesus is saying to him, "I am the Way and the Truth and the Life. No one is coming to the Father except through Me." (John 14:6)

When we hear the truth and believe, the truth sets us free from wasting our lives trying to save ourselves by the works of the law.Now we are aware that, whatever the law is saying, it is speaking to those under the law, that every mouth may be barred, and the entire world may become subject to the just verdict of God,

"...because, by works of law, no flesh at all shall be justified in His sight, for through law is the recognition of sin. Yet now, apart from law, a righteousness of God is manifest (being attested by the law and the prophets), yet a righteousness of God through Jesus Christ's faith, for all, and on all who are believing, for there is no distinction, for all sinned and are wanting of the glory of God. Being justified gratuitously in His grace, through the deliverance which is in Christ Jesus (Whom God purposed for a Propitiatory shelter, through faith in His blood, for a display of His righteousness because of the passing over of the penalties of sins which occurred before in the forbearance of God), toward the display of His righteousness in the current era, for Him to be just and a Justifier of the one who is of the faith of Jesus. Where, then, is boasting? It is debarred! Through what law?
Of works? No! But through faith's law. For we are reckoning a man to be justified by faith apart from works of law." (Romans 3:20-28)